You have a graphic open and are in Design or Test mode.
Make sure the Element Tree view is visible; from the bottom left side of the view, click Show all Elements.
The Element Tree now displays all elements and objects that are placed on the graphic.
With Layer (Layer1) selected, make sure that the Visible checkbox is checked.
The layer is visible in the Graphics Editor in Design and Test mode.
Navigate to the Properties view (Layer Properties), expand the General section, and in the Description field, type a name for the layer, for example, Wireframe or Background, etc. .
(Optional) Expand the Layer section, and from the Discipline drop–down menu select an associated discipline. In the future, when the graphic displays in the Graphics Viewer, you can sort the layers by discipline.
To add the image to the layer, do one of the following:
Click to import a standard image file.
Click to import an AutoCAD or XML file.
Drag a .CCG file and drop it over the Ribbon.
The wireframe or background image displays on the canvas.
In the Element Tree, next to the image entry, check the Lock checkbox to lock the image in place.
To create a layer for the Piping: a. In the Element Tree, click New Layer . b. Repeat Step 3 to name the layer. For example: Piping.
You now have a background layer that you can use to guide your pipe drawings. When the diagram is complete and you finalize the diagram, change the layer’s setting so that is not visible in Runtime mode.
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checkbox is checked. 
to import a standard image file. 
to import an AutoCAD or XML file. 
checkbox to lock the image in place. 
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